Coupling of propargylsilanes with Fischer carbene chromium complexes: a new synthesis of conjugated dienes

Patel, Paren P.; Zhu, Yifan; Zhang, Lei; Herndon, James W.

doi:10.1016/j.jorganchem.2004.07.051

Cited by 19 publications

(9 citation statements)

References 29 publications

(18 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, treatment of a-substituted, enantiopure allenylsilane ent-28 with enantiopure aldehyde ent-29 in the presence of TiCl 4 yielded homopropargylic al-cohol 30. [40] The product stereochemistry at C (3) can be traced back to the chelation controlled addition to the aldehyde, where a synclinal transition state (TS°) 31 with the electrophile approaching anti to the Si accounts for the C (4) stereochemistry (Scheme 8).…”

Section: Allenylsilanesmentioning

confidence: 99%

“…Organotrialkylsilanes manifest many desirable green attributes compared to traditional reactive carbon nucleophiles. From an organic synthesis perspective, they are not only stable to chromatography on silica gel4 but also tolerate a myriad of preparative conditions, such as air,5 moisture,6 reducing,7 and oxidizing8 conditions. This allows the silane to be installed onto a fragment at almost any stage in a synthesis.…”

Section: Stability Of Organotrialkylsilanesmentioning

confidence: 99%

See 1 more Smart Citation

Vinyl‐, Propargyl‐, and Allenylsilicon Reagents in Asymmetric Synthesis: A Relatively Untapped Resource of Environmentally Benign Reagents

Long¹,

Aye

2009

Chemistry A European J

100

View full text Add to dashboard Cite

An up-to-date in-depth review of the current virtues and limitations in the realm of carbonyl addition reactions with allenyl-, propargyl-, and vinylsilicon reagents, encompassing numerous practical as well as pedagogical principles is presented. Comparisons of chemo-, regio-, and stereoselectivity and reactivity are drawn. Synthetic applications and challenges associated with each class of organosilane are discussed threading together the prospects of these green carbanion surrogates.

show abstract

Section: Allenylsilanesmentioning

confidence: 99%

Section: Stability Of Organotrialkylsilanesmentioning

confidence: 99%

Vinyl‐, Propargyl‐, and Allenylsilicon Reagents in Asymmetric Synthesis: A Relatively Untapped Resource of Environmentally Benign Reagents

Long¹,

Aye

2009

Chemistry A European J

100

View full text Add to dashboard Cite

show abstract

“…50 However, an alternative pathway for the formation of the α regioisomer could be the 1,2-silyl shift in the η 2 -vinyl intermediate (ii). 49,51,52 In addition, the dehydrogenative silylation products, that also are frequently formed in catalytic systems using alkynes and/or hydrosilane with sterically demanding substituents, can be formed by β-reductive elimination from B. 37 In the particular case of Et 3 SiC≡CH, the no formation of the β-(Z)-vinylsilane isomer strongly suggest It is worth to mention that some methods for the regioselective production of 1,1-disubstituted vinylsilanes (α isomer) by direct trans addition have been recently described.…”

Section: Synthesis Of Neutral and Cationic Rhodium(i) Complexes Contamentioning

confidence: 99%

Rhodium(I) Complexes with Hemilabile N-Heterocyclic Carbenes: Efficient Alkyne Hydrosilylation Catalysts

et al. 2007

View full text Add to dashboard Cite

A series of alkylammonium-imidazolium chloride salts [RImH(CH 2) n NMe 2 ]Cl•HCl (R = Me, t-Bu, Mes, n = 2, 3) have been prepared by alkylation of 1-substituted imidazole compounds with the corresponding chloro-alkyl-dimethylamine hydrochloride. These salts are precursors for the synthesis of a library of rhodium (I) complexes containing amino-alkyl functionalized N-heterocyclic carbene (NHC) ligands with hemilabile character by varying the substituent on the heterocyclic ring and the length of the linker with the dimethylamino moiety. The monodeprotonation of alkylammoniumimidazolium salts with NaH in the presence of [{Rh(µ-Cl)(cod)} 2 ] gave the amino-imidazolium salts [RImH(CH 2) n NMe 2 ][RhCl 2 (cod)]. Further deprotonation with NaH under non anhydrous conditions gave the neutral complexes [RhCl(cod)(RIm(CH 2) n NMe 2)] in good yields. The abstraction of the chloro ligand by silver salts rendered the cationic complexes [Rh(cod)(κ 2 C,N-RIm(CH 2) 3 NMe 2)][BF 4 ] (R = Me, Mes) by coordination of the NMe 2 fragment of the sidearm of the functionalized NHC ligands. The catalytic activity of the rhodium complexes in the hydrosilylation of terminal alkynes using HSiMe 2 Ph has been investigated with Ph-C≡CH, t-Bu-C≡CH, n-Bu-C≡CH, and Et 3 Si-C≡CH as substrates. Higher activities were achieved using neutral complexes having small substituents at the heterocyclic ring (R = Me). Excellent selectivities in the β-(Z)-vinylsilane isomer were found in the hydrosilylation of 1hexyne and predominantly the β-(E) and α-bis(silyl)alkene isomers were obtained in the hydrosilylation of triethylsilylacetylene.

show abstract

“…In 2004, Herndon et al reported the addition of silyl substituted alkynes 5 with Fischer carbene chromium complexes 6 to give 2-silyl substituted 1,3-dienes 7 (Scheme 2). 7 The major isomers were (E,E) isomers.…”

Section: Synthesis Of Silyl-substituted 13-butadienesmentioning

confidence: 96%

Silyl-substituted 1,3-butadienes for Diels–Alder reaction, ene reaction and allylation reaction

Zhao

Zhang

2011

Chem. Commun.

View full text Add to dashboard Cite

Silyl-substituted 1,3-butadienes are useful building blocks and are readily applied in several types of reactions such as Diels-Alder reaction, ene reaction and allylation. They can also participate in different tandem reactions such as Diels-Alder/allylation, ene/allylation, ene/allylation/Diels-Alder reaction, ene/allylation/ene reaction and ene/allylation/Diels-Alder/allylation reaction. This feature article reviews the synthesis of silyl-substituted 1,3-butadienes, and their applications in the reaction types mentioned above, involving a tandem Diels-Alder/ene/allylation process. This article also introduces some reactions of alkenylsilanes and allylsilanes for comparison and discussion about the tandem reaction. The tandem reactions described in this article are a powerful tool to construct complicated multicyclic compounds with high selectivity and high efficiency.

show abstract

Coupling of propargylsilanes with Fischer carbene chromium complexes: a new synthesis of conjugated dienes

Cited by 19 publications

References 29 publications

Vinyl‐, Propargyl‐, and Allenylsilicon Reagents in Asymmetric Synthesis: A Relatively Untapped Resource of Environmentally Benign Reagents

Vinyl‐, Propargyl‐, and Allenylsilicon Reagents in Asymmetric Synthesis: A Relatively Untapped Resource of Environmentally Benign Reagents

Rhodium(I) Complexes with Hemilabile N-Heterocyclic Carbenes: Efficient Alkyne Hydrosilylation Catalysts

Silyl-substituted 1,3-butadienes for Diels–Alder reaction, ene reaction and allylation reaction

Contact Info

Product

Resources

About